COVID-19

According to the Centers for Disease Control, dental instruments are classified into three categories depending on the risk of transmitting infection. The classifications of critical, semicritical

and noncritical are based on the following criteria:

1) Critical instruments are those used to penetrate soft tissue or bone, or enter into or contact the bloodstream or other normally sterile tissue. They should be sterilized after each use. Sterilization is achieved by steam under pressure (autoclaving), dry heat, or heat/chemical vapor. Critical instruments include forceps, scalpels, bone chisels, scalers and surgical burs.

2) Semi-critical instruments are those that do not penetrate soft tissues or bone but contact mucous membranes or non-intact skin, such as mirrors, reusable impression trays and amalgam condensers. These devices also should be sterilized after each use. In some cases, however, sterilization is not feasible and, therefore, high-level disinfection is appropriate. A high-level disinfectant is registered with the U.S. Environmental Protection Agency (EPA) as a “sterilant/disinfectant” and must be labeled as such.

3) Non-critical instruments are those that come into contact only with intact skin such as external components of x-ray heads, blood pressure cuffs and pulse oximeters. Such devices have a relatively low risk of transmitting infection; and, therefore, may be reprocessed between patients by intermediate-level or low-level disinfection. An intermediate-level disinfectant is EPA-registered as a “hospital disinfectant” and will be labeled for “tuberculocidal” activity (e.g., phenolics, iodophors, and chlorine-containing compounds). A low-level disinfectant is EPA- registered as a “hospital disinfectant” but is not labeled for “tuberculocidal” activity (e.g., quaternary ammonium compounds). The tuberculocidal claim is used as a benchmark to measure germicidal potency. Germicides labeled as “hospital disinfectant”

without a tuberculocidal claim pass potency tests for activity against three representative microorganisms: Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella choleraesuis

Processing Instruments

We sterilize all critical and semicritical dental instruments that are heat stable after each use by steam under pressure (autoclaving), dry heat, or chemical vapor. Before sterilization or high-level disinfection, we clean our instruments to remove debris. Enzymatic and non-enzymatic solutions facilitate instrument cleaning. We use heavy- duty gloves when handling contaminated instruments. We soak instruments in water and/or disinfectant/detergent as soon as possible after use to prevent drying of debris. We use instrument cassettes and mechanical cleaning (e.g., ultrasonic cleaners) to reduce direct handling of contaminated instruments. We apply rust inhibitors to protect instruments from corrosion that may result from autoclaving. We package rinsed and dried instruments before sterilization to protect them from contamination after they are removed from the sterilizer and during transport chairside or to storage.